Triethylamine → Ethyl 3-(3-(benzyloxy)phenyl)-2-(3-(4-(tert-butoxycarbonylamino)benzyl)ureido)propanoate

Participants

Reaction Conditions

Reaction Steps

160 (530 mg, 1.76 mmol) was dissolved in AcOEt (30 mL) and trisphosgene (0.33 equivalent, 173 mg) was added while stirring at −10° C. The mixture was allowed to warm to room temperature, then refluxed for 1 h. 4-(tert-butoxycarbonylamino)benzylamine (391 mg, 1 equivalent) and triethylamine (2 equivalent) were added successively and the resulting solution was stirring at room temperature overnight. 100 ml of AcOEt are added. The organic phase are washed with 10% citric acid, saturated NaHCO3 and brine then dried over Na2SO4, filtered and concentrated. The crude product was purified by flash chromatography (AcOEt/Hexane 5/5) to afford 161 as white solid (960 mg, 99%). 1H NMR (DMSO): δ 1.28 (t, 3H, J=6.5 Hz), 1.61 (s, 9H), 3.01 (dd, 1H, J=13.8, 8.3 Hz), 3.09 (dd, 1H, J=13.8, 5.0 Hz), 4.19 (q, 2H, J=6.5 Hz), 4.24 (d, 2H, J=5.1 Hz), 4.57 (s, 1H), 5.20 (s, 2H), 6.38 (d, 1H, J=7.8 Hz), 6.61 (t, 1H, J=5.1 Hz), 6.90 (d, 1H, J=7.1 Hz), 7.02 (d, 1H, J=8.7 Hz), 7.21 (d, 2H, J=8.1 Hz), 7.33 (t, 1H, J=7.8 Hz), 7.50 (m, 5H), 7.57 (d, 2H, J=8.1 Hz), 9.35 (s, 1H).

Provenance & Evidence